Image guided medical and surgical procedures utilize patient images obtained prior to or during a medical procedure to guide a physician performing the procedure. Recent advances in imaging technology, especially in imaging technologies that produce highly-detailed, computer-generated two-dimensional and three-dimensional images, such as computed tomography (CT), magnetic resonance imaging (MRI), isocentric C-arm fluoroscopic imaging or two and three-dimensional fluoroscopes or ultrasounds have increased the interest in image guided medical procedures.
During these image guided medical procedures, the area of interest of the patient that has been imaged is displayed on a two-dimensional display. Surgical instruments that are used during this medical procedure are tracked and superimposed onto this two-dimensional display to show the location of the surgical instrument relative to the area of interest in the body. However, these two-dimensional displays are not capable of providing either five or six degrees of freedom information of the instrument or other devices navigated in the body, which may be information in certain medical procedures.
Other types of navigation systems operate as an image-less system, where an image of the body is not captured by an imaging device prior to the medical procedure. With this type of procedure, the system may use a probe to contact certain landmarks in the body, such as landmarks on bone, where the system generates either a two-dimensional or three-dimensional model of the area of interest based upon these contacts. This way, when the surgical instrument or other object is tracked relative to this area, they can be superimposed on this model. Here again, however, the display that illustrates the tracked medical instrument in relation to this model is not capable of providing five or six degree of freedom information.
Moreover, in certain medical procedures providing either a five or six degree of freedom display, will greatly assist the surgeon in the medical procedure. For example, this type of information may be helpful with minimally invasive procedures where clearance and viewing of the area of interest may not be relatively available. Therefore, during these types of procedures, the surgeon may not clearly know where the tip or orientation of the instrument may be relative to the patient. With flexible instruments, such as catheters, it makes it even more difficult to estimate where the tip or orientation of the catheter may be during these types of procedures.
Still other procedures, such as orthopedic procedures, employ implants that include multiple components that articulate with one another. Placement of one component of the implant relative to another component of the implant is critical. If a display can provide both targeting and six degree of freedom information in relation to these mutually dependent components, these procedures may be improved. For example, each implant component may require a specific orientation relative to its corresponding implant component to provide for the proper placement and proper range of motion. With these types of procedures and implants, it is generally difficult to accurately locate the components in the five or six degrees of freedom position. Since the orientation and location of these individual components is dependent upon one another to be effective, these components must be properly positioned and aligned in order to improve the life of the implant, increase the range of motion and provide superior patient outcomes.
It is, therefore, desirable to provide a display, which can provide five or six degrees of freedom alignment information regarding tracked surgical instruments and implants, particularly implants or devices that have several components each having a specific orientation dependent upon one another. It is, therefore, an object of the present invention to provide such a display to assist in medical procedures.